Aldoril

SIDE EFFECTS

The following adverse reactions
have been reported and, within each category, are listed in order of decreasing
severity.

Methyldopa

Sedation, usually transient, may
occur during the initial period of therapy or whenever the dose is increased.
Headache, asthenia, or weakness may be noted as early
and transient symptoms. However, significant adverse effects due to methyldopa
have been infrequent and this agent usually is well
tolerated.

DRUG INTERACTIONS

Methyldopa

When methyldopa is used with
other antihypertensive drugs, potentiation of antihypertensive effect may
occur. Patients should be followed carefully to detect side
reactions or unusual manifestations of drug idiosyncrasy.

Patients may require reduced
doses of anesthetics when on methyldopa. If hypotension does occur during anesthesia,
it usually can be controlled by vasopressors. The
adrenergic receptors remain sensitive during treatment with methyldopa.

When methyldopa and lithium are
given concomitantly the patient should be carefully monitored for symptoms of
lithium toxicity. Read the prescribing information
for lithium preparations.

Several studies demonstrate a
decrease in the bioavailability of methyldopa when it is ingested with ferrous
sulfate or ferrous gluconate. This may adversely
affect blood pressure control in patients treated with methyldopa.
Coadministration of methyldopa with ferrous sulfate or ferrous
gluconate is not recommended.

Hydrochlorothiazide

When given concurrently the
following drugs may interact with thiazide diuretics.

Alcohol, barbiturates, or narcotics— potentiation of orthostatic
hypotension may occur.

Antidiabetic drugs(oral agents and insulin) — dosage adjustment
of the antidiabetic drug may be required.

Other antihypertensive drugs— additive effect or potentiation.

Cholestyramine and colestipol resins— Absorption of hydrochlorothiazide
is impaired in the presence of anionic exchange resins. Single doses of either
cholestyramine or colestipol resins bind the hydrochlorothiazide and reduce
its absorption from the gastrointestinal tract by up to 85 and 43 percent, respectively.

Lithium— generally should not be given with diuretics.
Diuretic agents reduce the renal clearance of lithium and add a high risk of
lithium toxicity. Refer to the package insert for lithium preparations before
use of such preparations with ALDORIL (methyldopa-hydrochlorothiazide) .

Non-steroidal Anti-inflammatory Drugs— In some patients, the
administration of a non-steroidal anti-inflammatory agent can reduce the diuretic,
natriuretic, and antihypertensive effects of loop, potassium-sparing and thiazide
diuretics. Therefore, when ALDORIL (methyldopa-hydrochlorothiazide) and non-steroidal anti-inflammatory agents
are used concomitantly, the patient should be observed closely to determine
if the desired effect of the diuretic is obtained.

Drug/Laboratory Test Interactions

Methyldopa

Methyldopa may interfere with
measurement of: urinaryuric acid by the phosphotungstate method, serum creatinine by the alkaline picrate method, and SGOT by
colorimetric methods. Interference with spectrophotometric methods for SGOT
analysis has not been reported.

Since methyldopa causes
fluorescence in urine samples at the same wave lengths as catecholamines,
falsely high levels of urinary catecholamines may be reported.
This will interfere with the diagnosis of pheochromocytoma. It is important to
recognize this phenomenon before a patient with
a possible pheochromocytoma is subjected to surgery. Methyldopa does not
interfere with measurement of VMA
(vanillylmandelic acid), a test for pheochromocytoma, by those methods which
convert VMA to vanillin. Methyldopa is not recommended for
the treatment of patients with pheochromocytoma. Rarely, when urine is exposed
to air after voiding, it may darken because of
breakdown of methyldopa or its metabolites.

Hydrochlorothiazide

Thiazides should be discontinued before carrying out tests for parathyroid
function (see PRECAUTIONS, General).